In recent years, a memory card having a nonvolatile memory mounted thereon has been expanding its market as a recording medium of a digital camera and a cellular phone. With an increase in capacity of memory card, its use has been spreading from small capacity recording such as a data file and a still image to moving image recording that requires a large capacity. Therefore, conventionally, various designs have been tried on the recording medium having the nonvolatile memory mounted thereon (for example, patent documents 1 to 4).
The memory card of large capacity can save a large amount of data and can store various kinds of data, and therefore management information thereof is diversified. For example, the management information includes a metadata management file for accelerating file access, a file of a virtual directory structure in which the information is managed by types of data, and a database type file system different from the conventional FAT file system. An object of such management information is to facilitate management. Such diversified management information has small size, and thus it causes a factor of increasing a frequency of data writing for each sector as a result.
Patent document 1: JP-A-2001-154909
Patent document 2: JP-A-11-53248
Patent document 3: JP-A-2002-324008
Patent document 4: JP-A-05-216780